Ajụjụ Ihe Nlereanya Na-ekwu Maka Diode Na-ewepụta Ọkụ (LED)
Diode na-ewepụta ìhè (LED) bụ ngwaọrụ semiconductor nke na-ewepụta ìhè mgbe ọkụ eletrik na-agafe na ya. Ihe a na-ahụ n'azụ LEDs bụ electroluminescence, ebe ihe semiconductor na-ewepụta ìhè mgbe ọkụ eletrik kpaliri ya. LEDs aghọwo ihe a ma ama n'ọtụtụ ojiji n'ihi arụmọrụ dị elu ha na ogologo ndụ ha ma e jiri ya tụnyere isi mmalite ọkụ ọdịnala dịka bọlbụ incandescent.
N'isiokwu a, anyị ga-atụle ụfọdụ ihe atụ nke nsogbu metụtara LEDs ma kọwaa azịza ha na mkparịta ụka ha nke ọma iji nyere aka ịghọta echiche dị n'azụ ihe a.
Ajụjụ Ihe Nlereanya nke 1: Njirimara Ndị Dị Mkpa nke LEDs
Ajụjụ: LED nwere ike ịpụta ìhè site na ogologo ebili mmiri nke 650 nm (nanometers). Gbakọọ ike nke foton nke LED a na-ewepụta na volt elektrọn (eV).
Azịza:
Enwere ike ịgbakọ ike foton site na iji usoro Planck:
\[ E = \frac{hc}{\lambda} \]
Ebe:
– \(E \) bụ ike foton,
– \(h \) bụ ihe Planck na-agbanwe agbanwe (\(6.626 \times 10^{-34} \text{ Js}\)),
– \(c \) bụ ọsọ nke ìhè (\(3 \u003 10^8 \text{ m/s}\)),
– \( \lambda \) bụ ogologo ebili mmiri nke ìhè (650 nm ma ọ bụ \(650 \times 10^{-9} \text{ m}\)).
Ịtinye ụkpụrụ ndị a n'ime usoro ahụ na-emepụta:
\[
E = \frac{6.626 \ugboro 10^{-34} \ugboro 3 \ugboro 10^8}{650 \ugboro 10^{-9}}
= \frac{1.9878 \ugboro 10^{-25}}{650 \ugboro 10^{-9}}
= 3.05 \ugboro 10^{-19} \ederede{ J}
\]
Na-esote, anyị na-agbanwe Joules ka ọ bụrụ elektrọn-volt site na iji ntụgharị \(1 \text{eV} = 1.602 \times 10^{-19} \text{ J}\):
\[
E = \frac{3.05 \ugboro 10^{-19}}{1.602 \ugboro 10^{-19}}
≈ 1.90 \ederede{eV}
\]
Ya mere, ike foton nke LED nwere ogologo ebili mmiri nke 650 nm na-ewepụta bụ ihe dịka 1.90 eV.
Ihe atụ nke abụọ: Voltaji LED n'ihu
Ajụjụ: LED uhie nwere voltaji n'ihu nke 2V ma chọọ ka ọkụ eletrik nke 20 mA rụọ ọrụ nke ọma. Gbakọọ ike LED na-eri.
Azịza:
Iji gbakọọ ike nke LED na-etinye, anyị na-eji usoro nhazi maka ike, ya bụ:
\[ P = V \ugboro I \]
Ebe:
– \( P \) bụ ike dị na Watts (W),
– \(V \) bụ voltaji dị na Volts (V),
– \( I \) bụ ọkụ eletrik dị na Amperes (A).
Tinye ụkpụrụ ndị a n'ime usoro:
\[
P = 2 \ederede{ V} \oge 20 \ederede{ mA}
= 2 \ederede{ V} \oge 0.02 \ederede{ A}
= 0.04 \ederede{ W}
\]
Ya mere, ike nke LED uhie na-arụ ọrụ na voltaji n'ihu nke 2V na ugbu a nke 20 mA bụ 0.04 Watts.
Ihe atụ nke atọ: Ịrụ ọrụ nke LED
Ajụjụ: LED na-acha anụnụ anụnụ nwere arụmọrụ quantum nke 30%. Ọ bụrụ na LED na-eji 0.1 W nke ike eletriki, kedu ike a na-ewepụta dị ka ìhè?
Azịza:
Arụmọrụ nke quantum (η) bụ oke nke ike ewepụtara n'ụdị ìhè (P_luminous) na ntinye ike eletriki (P_input):
\[ η = \frac{P_{\text{luminous}}}{P_{\text{input}}} \]
Iji chọta \(P_{\text{luminous}} \), jiri usoro ndị a nwere uru arụmọrụ nke 30% ma ọ bụ 0.30:
\[
0.30 = \frac{P_{\text{luminous}}}{0.1 \text{ W}}
\]
N'ihi ya:
\[
P_{\text{luminous}} = 0.30 \ugboro 0.1 \text{ W}
= 0.03 \ederede{ W}
\]
Ya mere, ike nke LED wepụtara n'ụdị ìhè bụ 0.03 Watt.
Ihe atụ Nsogbu nke 4: Sekọnd LED nke usoro
Ajụjụ: I nwere LED atọ nwere voltaji n'ihu nke 2V nke ọ bụla kwesịrị ijikọ n'usoro. Ọ bụrụ na isi iyi voltaji ahụ bụ 9V, chọpụta uru nke resistor achọrọ iji belata ike ọkụ eletrik na 20 mA.
Azịza:
Mgbe ejikọtara LED n'usoro, mkpokọta voltaji achọrọ bụ mkpokọta voltaji ndị na-aga n'ihu nke LED ọ bụla:
\[
V_{ngụkọta} = V_f1 + V_f2 + V_f3
= 2V + 2V + 2V
= 6V
\]
Voltaji fọdụrụnụ nke resistor ga-ewepụ bụ:
\[
V_{R} = V_{isi iyi} – V_{mkpokọta}
= 9V – 6V
= 3V
\]
Site na ọkụ achọrọ nke 20 mA, a na-agbakọ uru resistor site na iji Iwu Ohm:
\[
R = \frac{V_{R}}{I}
= \frac{3V}{20 \ederede{ mA}}
= \frac{3V}{0.02A}
= 150 \Omega
\]
Ya mere, uru resistor achọrọ bụ 150 ohms.
Ihe atụ nke 5: Sekit Oke Mmiri nke LED nke Parallel
Ajụjụ: N'ime sekit, e nwere LED abụọ e doziri n'otu oge, nke ọ bụla nwere voltaji n'ihu nke 2V na ugbu a nke 20 mA. Gịnị bụ mkpokọta ugbu a achọrọ site na isi iyi voltaji 5V ma ọ bụrụ na ejiri resistor mee ihe maka LED ọ bụla?
Azịza:
Maka LED ndị a haziri n'otu oge, LED ọ bụla ga-enweta otu voltaji ahụ, ya bụ voltaji ha na-aga n'ihu, ebe ọ bụ na ha chọrọ 20 mA nke ugbu a kwa LED, mkpokọta ugbu a bụ:
\[
I_{mkpokọta} = I_1 + I_2
= 20 \ederede{mA} + 20 \ederede{mA}
= 40 \ederede{ mA}
\]
Iji gbakọọ uru resistor maka LED ọ bụla:
\[
V_{R} = V_{isi iyi} – V_f
= 5V – 2V
= 3V
\]
Uru resistor iji belata oge dị na LED ọ bụla bụ:
\[
R = \frac{V_{R}}{I}
= \frac{3V}{20 \ederede{ mA}}
= \frac{3V}{0.02A}
= 150 \Omega
\]
Ya mere, LED ọ bụla chọrọ ihe mgbochi 150 ohm. Oke ọkụ achọrọ site na ihe nkwado ike 5V bụ 40 mA.
Mmechi
LED bụ ihe dị oke mkpa na ngwa eletrọniki ọgbara ọhụrụ n'ihi ikike ha nwere inye ọkụ dị oke mma na ndụ ogologo oge. Ịghọta echiche ndị bụ isi dịka voltaji forward, current, power, quantum efficiency, na otu esi ahazi ha na sekit ga-enye ntọala siri ike maka ngwa bara uru. Ihe atụ ndị dị n'elu bụ nzọụkwụ mbụ iji mụta ngwa na mgbakọ dị iche iche metụtara ojiji nke LED na sekit eletrọniki.
